Ishii Wataru, Matsuda Masayuki, Nakamura Akinori, Nakamura Naoshi, Suzuki Akio, Ikeda Shu-ichi
Third Department of Medicine, Shinshu University School of Medicine, Matsumoto.
Intern Med. 2003 Sep;42(9):800-5. doi: 10.2169/internalmedicine.42.800.
To detect amyloid deposits in the early phase of illness, we investigated the usefulness of abdominal fat aspiration biopsy along with genotyping of serum amyloid A (SAA) in patients with rheumatoid arthritis (RA).
We performed abdominal fat aspiration biopsy with phenol Congo red staining and determined inflammatory markers, including CRP and SAA, in 217 patients with an RA history longer than 5 years (mean age, 64.1 +/- 10.6 years). Genotypes of SAA1 and 2 were investigated in 127 patients with RA by a polymerase chain reaction-restriction fragment length polymorphism analysis.
In the abdominal fat aspiration biopsy 17 patients (7.8%) demonstrated amyloid deposits, which were confirmed as AA type by immunostaining on biopsied tissues from other organs, and nine of them showed no clinical symptoms ascribable to amyloidosis. RA patients with amyloidosis showed significantly higher serum levels of CRP (p < 0.05) and SAA (p < 0.0001) than those without amyloidosis. In the genotyping, amyloid deposition was significantly correlated with the frequency of SAA1.3 (p < 0.005 vs. 1.1, p < 0.05 vs. 1.5). Comparison of inflammatory markers between the number of SAA1.3 alleles showed that the SAA/CRP ratio and SAA concentration were higher in the 1.3 homozygote than in the others (p < 0.05). Two patients demonstrated amyloid deposits at the second abdominal fat biopsy one year after the first, and their SAA1 genotypes were 1.3/1.5 and 1.3/1.3.
In RA patients confirmed as having SAA1.3, serial examinations with abdominal fat aspiration biopsy might contribute greatly to the early detection of amyloidosis during the long-term follow-up.
为了在疾病早期检测淀粉样沉积物，我们研究了腹部脂肪抽吸活检联合血清淀粉样蛋白A（SAA）基因分型在类风湿关节炎（RA）患者中的应用价值。
我们对217例病程超过5年（平均年龄64.1±10.6岁）的RA患者进行了腹部脂肪抽吸活检及酚刚果红染色，并测定了包括CRP和SAA在内的炎症标志物。通过聚合酶链反应-限制性片段长度多态性分析对127例RA患者的SAA1和2基因型进行了研究。
在腹部脂肪抽吸活检中，17例患者（7.8%）显示有淀粉样沉积物，经其他器官活检组织免疫染色确认为AA型，其中9例无淀粉样变性相关临床症状。有淀粉样变性的RA患者血清CRP水平（p<0.05）和SAA水平（p<0.0001）显著高于无淀粉样变性的患者。在基因分型中，淀粉样沉积与SAA1.3的频率显著相关（与1.1相比，p<0.005；与1.5相比，p<0.05）。比较不同SAA1.3等位基因数量患者的炎症标志物，发现1.3纯合子的SAA/CRP比值和SAA浓度高于其他患者（p<0.05）。2例患者在首次腹部脂肪活检1年后的第二次活检时出现淀粉样沉积物，其SAA1基因型分别为1.3/1.5和1.3/1.3。
在确诊为SAA1.3的RA患者中，长期随访期间通过腹部脂肪抽吸活检进行系列检查可能对淀粉样变性的早期检测有很大帮助。
